JP3640837B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention supplies a processing solution such as a chemical solution or pure water to the surface of a substrate such as a semiconductor wafer, a glass substrate for liquid crystal display or a photomask substrate, and performs a predetermined process such as a chemical cleaning process or a pure water cleaning process. The present invention relates to a substrate processing apparatus.
[0002]
[Prior art]
In the manufacturing process of a semiconductor device, a chemical liquid such as hydrofluoric acid (HF) serving as a first processing liquid is supplied to the surface of the wafer while rotating a semiconductor wafer (hereinafter simply referred to as “wafer”) which is a kind of substrate. A chemical cleaning process is performed, and then a pure water serving as a second processing liquid is supplied to perform the pure water cleaning process. Further, a drying process is performed in which the wafer is rotated at a high speed to dry the surface of the wafer.
[0003]
A conventional substrate processing apparatus that performs such a series of processing is a spin chuck that rotatably holds a wafer, a first nozzle that supplies a chemical to the surface of the wafer held by the spin chuck, and a spin chuck that holds the chemical solution. A second nozzle for supplying pure water to the surface of the wafer, and a recovery member (splash card) having an inclined portion for recovering the chemical solution and pure water around the wafer held by the spin chuck. I have.
[0004]
In addition, an opening for introducing gas into the recovery member and for loading and unloading the wafer with respect to the recovery member is formed above the recovery member, and a lower portion for recovering chemicals and pure water. A treatment liquid recovery path is provided.
[0005]
A series of processes such as a chemical cleaning process, a pure water cleaning process, and a drying process are conventionally performed as follows.
That is, a chemical cleaning process is performed by supplying a chemical from the first nozzle to the surface of the wafer while rotating the spin chuck holding the wafer while the recovery member is arranged around the wafer held by the spin chuck. Is done. At this time, the chemical liquid splashed from the outer periphery of the wafer with the rotation of the wafer is received and collected by the collecting member and discharged through the processing liquid collecting path.
[0007]
Next, after the chemical solution cleaning process using the chemical solution, while the recovery member is continuously disposed around the wafer held by the spin chuck, the wafer is discharged from the second nozzle while rotating the spin chuck holding the wafer. Pure water is supplied to the surface of the substrate to perform a pure water cleaning process. At this time, pure water scattered from the outer periphery of the wafer as the wafer rotates is received by the recovery member, recovered, and discharged through the processing liquid recovery path.
[0008]
When the pure water cleaning process is completed, the supply of pure water from the second nozzle to the surface of the wafer is stopped, and the wafer is removed while the recovery member is disposed around the wafer held by the spin chuck. The wafer is dried by continuing the rotation of the held spin chuck. It should be noted that most of the pure water remaining on the surface of the wafer is scattered from the outer periphery of the wafer at the initial stage of the drying process after the supply of the chemical solution or pure water to the wafer from the first nozzle or the second nozzle is stopped. At this stage, the wafer is in a damp state where droplets remain at the molecular level, so the wafer is rotated for a time sufficient for the wafer to dry completely. The drying process is performed. Further, in order to sufficiently dry the wafer, the drying process usually rotates the spin chuck at a higher speed than the chemical cleaning process and the pure water cleaning process.
[0009]
[Problems to be solved by the invention]
However, in the conventional substrate processing apparatus, when the chemical solution cleaning process is performed, the chemical solution scatters around as the wafer rotates, so that the mist droplets of the chemical solution are collected on the outer wall surface of the inclined portion of the recovery member. There is a problem of adhering to the (back side). The droplets adhering to the outer wall surface of the recovery member accumulate in the chamber of the substrate processing apparatus and become a contamination source for the wafer that is subjected to the drying process.
[0010]
For this reason, in order to remove the contamination source of the wafer, it is necessary to periodically clean the droplets adhering to the outer wall surface of the recovery member.
[0011]
Therefore, as an apparatus for cleaning the outer wall surface of the inclined portion of the recovery member, an apparatus provided with a dedicated nozzle or the like can be considered. However, in this apparatus, since the collecting member is usually in a cylindrical shape, a plurality of separate dedicated nozzles must be provided above and around the collecting member, resulting in high costs. In addition, if the periodic cleaning is performed, the operation rate of the substrate processing apparatus is lowered.
[0012]
The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a substrate processing apparatus that can clean the outer wall surface of the inclined portion of the recovery member and remove the contamination source of the substrate with a simple configuration. To do.
[0013]
In order to solve the above problems, a substrate processing apparatus according to claim 1, a substrate processing apparatus for performing predetermined processing on a substrate in the processing chamber, a substrate holding device for holding a substrate in the processing chamber, the substrate A first driving means for rotating the substrate holding means holding the substrate, a first supply means for supplying a chemical to the surface of the substrate held by the substrate holding means, and an outer periphery of the substrate as the substrate rotates. A collecting member having an inclined portion for collecting the scattered chemical solution ; a first state in which the inclined portion of the collecting member is positioned on the outer periphery of the substrate holding means; and the substrate holding means at a position above the inclined portion of the collecting member. A second driving means for relatively moving the substrate holding means and the recovery member so that the surface of the substrate held in the second state is located; and the substrate holding in the second state Of the substrate held in the means A second supply means for supplying pure water to the surface, the recovery member and the pure water recovery passage formed between the inner wall surface of the processing chamber, said first driving means, said first supply means, said first (B) a pure water cleaning process for supplying pure water while rotating the substrate at the first rotational speed in the second state; and (b) controlling the operation of the two driving means and the second supply means. In the second state, pure water is supplied to the outer wall portion of the inclined portion of the recovery member by decelerating the rotation of the substrate to a second rotational speed lower than the first rotational speed while supplying pure water. And a controller that performs an inclined portion cleaning process for discharging pure water through the pure water recovery path . In addition, in the case of “holding the substrate” herein, when the holding member or the like holds the end portion of the substrate, when the back surface of the substrate is sucked and held by suction holding means or the like, the back surface of the substrate is The case where it is held while being supported by a plurality of support members is included. Further, it is desirable that the recovery member is disposed around the substrate holding means.
[0016]
The substrate processing apparatus according to claim 2 is the substrate processing apparatus according to claim 1 , wherein the first driving unit supplies pure water to the surface of the substrate by the second supply unit in the second state. After the supply, the substrate holding means holding the substrate in the second state is rotated at a third rotational speed higher than the first rotational speed and the second rotational speed.
[0017]
The substrate processing apparatus according to claim 3 is the substrate processing apparatus according to claim 1 or 2 , wherein the second driving unit moves the collection member in the vertical direction with respect to the substrate holding unit. It is characterized by making it.
[0018]
The substrate processing apparatus according to claim 4 is the substrate processing apparatus according to claim 1 or 2 , wherein the second driving unit moves the substrate holding unit in a vertical direction with respect to the recovery member. It is characterized by making it.
[0020]
A substrate processing apparatus according to a fifth aspect is the substrate processing apparatus according to any one of the first to fourth aspects, wherein the first supply unit and the second supply unit are a single supply unit. It is also used as a combination.
[0021]
A substrate processing apparatus according to a sixth aspect is the substrate processing apparatus according to any one of the first to fifth aspects , wherein an opening for transporting the substrate is provided at a side portion of the processing chamber. And the height of the substrate holding means in the second state and the opening of the processing chamber are the same.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of a substrate processing apparatus according to the present invention. This substrate processing apparatus is a cleaning / drying apparatus that performs a chemical cleaning process using a chemical, a pure water cleaning process using pure water, and a drying process that performs spin drying on a wafer, which is a kind of substrate.
[0023]
The substrate processing apparatus is held by a spin chuck 10 that rotatably holds a wafer W, a recovery member (splash guard) 20 that recovers chemicals and the like scattered on the outer periphery of the wafer W as the wafer W rotates, and the spin chuck 10. A nozzle 40 or the like for supplying a chemical solution or a pure water as a cleaning solution is provided in the chamber 40 as a processing chamber on the upper surface of the wafer W.
[0024]
In the spin chuck 10, a disk-like spin base 13 is connected to an upper end portion of a rotating shaft 12 that is rotated around an axis J in a vertical direction by an electric motor 11 corresponding to a first driving unit so as to be integrally rotatable. . The electric motor 11 is provided outside the chamber 40 and below the chamber 40, and the rotation speed can be changed as appropriate. The electric motor 11 may be provided in the chamber 40.
[0025]
Three or more holding members 14 are provided on the upper surface of the spin base 13, and only two holding members 14 are shown in FIG. Each holding member 14 has a support portion 14a that supports the outer peripheral portion of the wafer W across the upper surface of the spin base 13, and a holding portion 14b that presses and holds the outer peripheral edge of the wafer W supported by the support portion 14a. I have. The holding member 14 holds the wafer W apart from the upper surface of the spin base 13. Each holding portion 14b can be switched between a state in which the outer peripheral edge of the wafer W is pressed and held and a state in which the holding is released from the outer peripheral edge of the wafer W.
[0026]
The recovery member 20 has a cylindrical shape that is substantially rotationally symmetric with respect to an axis J passing through the center of the rotary shaft 12. On the upper tip side of the recovery member 20, there is an inclined portion 21 inclined toward the spin chuck 10 side. The inner wall surface 22 side of the inclined portion 21 of the recovery member 20 serves as a chemical solution guide portion, and a substantially cylindrical chemical solution recovery path 23 is formed on the inner periphery of the inner wall surface 22. On the other hand, a pure water recovery path 25 is formed between the outer wall surface 24 of the inclined portion 21 of the recovery member 20 and the inner wall surface of the chamber 40.
[0027]
The collection member 20 can be moved up and down by an elevating mechanism 26 constituted by a well-known uniaxial driving mechanism such as a ball screw. The elevating mechanism 26 is provided outside the chamber 40 and below the chamber 40. By the drive control of the elevating mechanism 26, the recovery member 20 has the most advanced portion H1 as shown by the solid line in FIG. The leading edge as shown by the position and the two-dot chain line in FIG. 1 is switched to the position of H2. The time when the recovery member 20 is at the position H1 corresponds to the second state, and the time when the recovery member 20 is at the position H2 corresponds to the first state.
[0028]
The nozzle 30 is provided above the wafer W holding the spin chuck 10 in the chamber 40. The nozzle 30 is connected to a chemical solution supply source (not shown) through a supply pipe 31 and a supply pipe 32, and supplies the chemical liquid to the surface of the wafer W. Examples of the chemical solution include hydrofluoric acid, ammonia, and the like, but a liquid mixture composed of ammonia water, hydrogen peroxide solution, and water may be used. The supply and stop of the chemical liquid from the nozzle 30 to the surface of the wafer W are performed by opening / closing control of an opening / closing valve 33 provided in the middle of the supply pipe 32. The nozzle 30 is connected to a pure water supply source (not shown) via a supply pipe 31 and a supply pipe 34, and supplies pure water to the surface of the wafer W. Supply and stop of pure water from the nozzle 30 to the surface of the wafer W are performed by opening / closing control of an opening / closing valve 35 provided in the middle of the pipe 34.
[0029]
On the side of the chamber 40, a loading / unloading port 41 corresponding to an opening for loading / unloading the wafer W into / from the chamber 40 is formed corresponding to the height of the spin base 13. ing. The carry-in / out entrance 41 is provided with a shutter 42 that opens and closes the carry-in / out entrance 41. A hole 43 for the supply pipe 31 is formed in the upper part of the chamber 40.
[0030]
Further, a hole 44 for discharging the chemical solution from the chamber 40 is formed at the bottom of the chamber 40 corresponding to the chemical solution recovery path 23. A discharge pipe 45 is connected to the hole 44, and the chemical solution is discharged out of the chamber 40 through the discharge pipe 45. The discharge of the chemical solution and the stop thereof are performed by opening / closing control of the opening / closing valve 46 provided in the middle of the discharge pipe 45. Further, a hole 47 for discharging pure water from the chamber 40 is formed at the bottom of the chamber 40 corresponding to the pure water recovery path 25. A discharge pipe 48 is connected to the hole 47, and pure water is discharged out of the chamber 40 through the discharge pipe 48. The pure water is discharged and stopped by open / close control of an open / close valve 49 provided in the middle of the discharge pipe 48.
[0031]
A hole for the rotating shaft 12 that is sealed with respect to the rotating shaft 12 is formed at the bottom of the chamber 40.
[0032]
FIG. 2 is a block diagram showing the configuration of the control system of the substrate processing apparatus.
Control of rotation of the spin chuck 1 by the electric motor 11, control of raising and lowering the recovery member 20 by the lifting mechanism 26, control of supply and stop of the chemical solution supplied from the nozzle 30 by control of opening and closing of the on-off valve 33, control of opening and closing of the on-off valve The supply of pure water supplied from the nozzle 30 and its stop control, the holding of the wafer W by the holding part 14b of the spin chuck 10 and the release control thereof, and the opening and closing control of the on-off valve 46 are discharged from the chemical solution discharge passage 23. The controller 50 controls the discharge and stop of the chemical solution, the discharge of pure water discharged from the pure water discharge passage 25 by the opening and closing control of the on-off valve 49, the control of the stop, the opening and closing control of the shutter 41, and the like. The control unit 50 is constituted by a computer having a CPU, a memory, and the like.
[0033]
Next, the processing operation of the substrate processing apparatus will be described. FIG. 3 is a flowchart showing the processing operation of the substrate processing apparatus of the present invention, and FIGS. 4 and 5 are diagrams showing the positional relationship between the wafer and the recovery member during the processing operation of the substrate processing apparatus. 4 and 5, the electric motor 11, the spin base 3, and the holding member 14 are omitted for convenience.
[0034]
First, in a state where the shutter 41 is opened by the control unit 50, the wafer W is loaded into the chamber 40 by a substrate transfer mechanism (not shown), and the wafer W is held by the holding unit 14b (step S1). At this time, the recovery member 20 is in the position H1 (second state) shown in FIG. 1, and the positional relationship between the wafer W and the recovery member 20 is in the state shown in FIG. Next, the control unit 50 closes the shutter 41 and drives the elevating mechanism 26 to raise the collection member 20 (step S2). In this state, as shown in FIG. 4B, the recovery member 20 is in the position H2 (first state) shown in FIG.
[0035]
And the control part 50 drives the electric motor 11, and starts rotation of the wafer W (step S3). When the rotation of the wafer W is started, the on / off valve 33 is opened by the control unit 50, the supply of the chemical liquid from the nozzle 30 to the surface of the wafer W is started, and the chemical liquid cleaning process of the surface of the wafer W is performed. Is called. (Step S4). The state at this time is the state shown in FIG. 4C, and the rotation speed of the wafer W is 250 rpm to 350 rpm. Further, the chemical liquid scattered on the outer periphery of the wafer W with the rotation of the spin base 13 and the wafer W causes the control unit 50 to open the open / close valve 46 to open the chemical liquid recovery path 23, the hole 44 and the discharge pipe 45. And is discharged out of the chamber 40. When a predetermined time has elapsed since the supply of the chemical solution to the surface of the wafer W is started, the control unit 50 closes the on-off valve 33 and stops the supply of the chemical solution to the surface of the wafer W (step S5). . The state at this time is shown in FIG. 4D, and the wafer W is in a state where the rotation is continued at a rotational speed of 250 rpm to 350 rpm. Thereby, the chemical | medical solution washing process by step S4 and step S5 is complete | finished.
[0036]
Next, the controller 50 drives the elevating mechanism 26 to lower the collection member 20 (step S6). At this time, the recovery member 20 is at the position H2 shown in FIG. 1, and the positional relationship between the wafer W and the recovery member 20 is in the state shown in FIG. When the recovery member 20 is lowered, the on / off valve 35 is opened by the control unit 50, the supply of pure water from the nozzle 30 to the surface of the wafer W is started, and a pure water cleaning process is performed (step S7). . The state at this time is the state shown in FIG. 5B, and the rotational speed of the wafer W is about 250 rpm to 350 rpm (first rotational speed).
[0037]
Further, the control unit 50 controls the electric motor 11 to reduce the number of rotations of the wafer W (step S8). For example, the rotation speed of the wafer W is changed to 100 to 200 rpm (second rotation speed). As a result, pure water is reliably supplied to the outer wall portion 24 of the inclined portion 22 of the recovery member 20, and the mist droplets adhering to the outer wall portion 24 are washed with pure water. Further, the pure water scattered on the outer periphery of the wafer W with the rotation of the spin base 13 and the wafer W causes the controller 50 to open the open / close valve 49 and discharge the pure water recovery path 25, the hole 47 and the pure water. It is discharged out of the chamber 40 through the tube 48. When the supply of pure water to the surface of the wafer W is started and a predetermined time has elapsed, the controller 50 sets the on-off valve 35 to the “closed” state and stops the supply of pure water to the surface of the wafer W ( Step S9). Thereby, the pure water washing | cleaning process and inclination part washing | cleaning process which followed from step S7 to step S9 are complete | finished.
[0038]
When step S9 ends, the control unit 50 controls the electric motor 11 to increase the number of rotations of the wafer W (step S10). For example, the rotation speed of the wafer W is changed to 1000 rpm to 2000 rpm (third rotation speed). The state at this time is as shown in FIG. 5C, and the pure water adhering to the surface of the wafer W is spun off around the wafer W as the wafer W rotates at high speed, A drying process is performed. When the high-speed rotation of the wafer W elapses for a predetermined time, the control unit 50 controls the electric motor 11 to stop the rotation of the wafer W (step S11). Thereby, the drying process of the wafer W by step S10 and step S11 is complete | finished. The state at this time is a state as shown in FIG.
[0039]
Finally, the control unit 50 opens the shutter 41 and unloads the wafer W out of the chamber 40 by a substrate transfer mechanism (not shown) (step S12). At this time, since the loading / unloading port 41 is formed on the side portion of the chamber 40 so as to correspond to the height substantially equal to the position of the spin base 13, it is possible to move from the inside of the chamber 40 without moving the recovery member 20. The wafer W is unloaded smoothly. Thus, a series of processing operations of the substrate processing apparatus is completed.
[0040]
The substrate processing apparatus according to the present invention described above has the following effects.
[0041]
First, after performing the chemical solution cleaning process in step S4 and step S5, the drive mechanism 26 lowers the recovery member 20 from the H2 position (first state) to the H1 position (second state). In S7, the opening / closing valve 35 is set to the “open” state by the control unit 50, and the supply of pure water from the nozzle 30 to the surface of the wafer W is started, so that the pure water cleaning process for the surface of the wafer W is performed with a simple configuration. In addition, the cleaning process of the outer wall surface 24 of the inclined portion 21 can be performed simultaneously. As a result, if the outer wall surface 24 of the inclined portion 21 can be cleaned, the contamination source of the wafer W can be reliably removed.
[0042]
When performing the pure water cleaning process on the surface of the wafer W, the rotation speed of the wafer W is set to 250 rpm to 350 rpm (first rotation speed) as the first stage, and the rotation speed of the wafer W is set to 100 rpm as the second stage. If it is set to ˜200 rpm (second rotation speed), the surface of the wafer W can be surely cleaned with pure water in the first stage, and further, the surface of the wafer W and the outside of the inclined portion 21 of the recovery member 20 can be removed in the second stage. The wall surface 24 can be reliably washed with pure water.
[0043]
In addition, the relative positional relationship between the recovery member 20 and the spin base 13 can be switched with a simple configuration in which the recovery member 20 is moved in the vertical direction by the drive mechanism 26. Although not shown, the same effect can be obtained by moving the spin base 13 in the vertical direction instead of moving the recovery member 20 in the vertical direction.
[0044]
In addition, since the nozzle 30 serves both as a chemical solution supply and a pure water supply, a simple configuration of one nozzle performs a process on a series of wafers W of a chemical solution cleaning process, a pure water cleaning process, and a spin drying process. be able to.
[0045]
Further, since the loading / unloading port 41 for loading / unloading the wafer W is formed in the side portion of the chamber 40 so as to correspond to the height substantially equal to the position of the spin base 13, the series of the wafers W described above. After the above process is completed, the wafer W can be smoothly unloaded from the chamber 40.
[0046]
In the above-described embodiment of the present invention, the recovery member 20 is described as a cylindrical splash guard. However, the spin cup that receives the processing liquid scattered on the outer periphery of the wafer W on the recovery member 20 is described. May be used.
[0047]
【The invention's effect】
As described above in detail, according to the present invention, the second driving means holds the substrate from the first state where the inclined portion of the collecting member is positioned on the outer periphery of the substrate holding means to a position above the inclined portion of the collecting member. The substrate holding means and the recovery member are moved relative to each other so that the surface of the substrate held by the means is located, and held in the substrate holding means by the second supply means in the second state. Since pure water different from the chemical solution is supplied to the surface of the substrate, the outside of the inclined portion of the recovery member can be cleaned and the contamination source of the substrate can be removed with a simple configuration.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an embodiment of a substrate processing apparatus according to the present invention.
FIG. 2 is a block diagram showing a configuration of a control system of the substrate processing apparatus.
FIG. 3 is a flowchart showing a processing operation of the substrate processing apparatus of the present invention.
FIG. 4 is a diagram showing a positional relationship between a wafer and a recovery member during a processing operation of the substrate processing apparatus.
FIG. 5 is a diagram showing a positional relationship between a wafer and a recovery member during a processing operation of the substrate processing apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Spin chuck 11 Electric motor 13 Spin base 14 Holding member 20 Recovery member 21 Inclination part 24 Outer wall surface 26 Elevating mechanism 30 Nozzle 40 Chamber 41 Unloading / inlet port 50 Control part W Wafer H1 1st position (2nd state)
H2 second position (first state)

Claims (6)

A substrate processing apparatus for performing predetermined processing on a substrate in a processing chamber ,
Substrate holding means for holding the substrate in the processing chamber ;
First driving means for rotating the substrate holding means holding the substrate;
First supply means for supplying a chemical to the surface of the substrate held by the substrate holding means;
A recovery member having an inclined portion for recovering the chemical liquid scattered on the outer periphery of the substrate along with the rotation of the substrate;
A first state in which the inclined portion of the collecting member is located on the outer periphery of the substrate holding means, and a second state in which the surface of the substrate held by the substrate holding means is located at a position above the inclined portion of the collecting member. Second driving means for relatively moving the substrate holding means and the recovery member,
Second supply means for supplying pure water to the surface of the substrate held by the substrate holding means in the second state;
A pure water recovery path formed between the recovery member and the inner wall surface of the processing chamber;
By controlling the operation of the first drive means, the first supply means, the second drive means, and the second supply means, (a) the substrate is rotated at a first rotational speed in the second state. (B) decelerating the rotation of the substrate to a second rotational speed that is lower than the first rotational speed while supplying pure water in the second state. A control unit that supplies pure water to the outer wall portion of the inclined portion of the recovery member and discharges the pure water through the pure water recovery path;
A substrate processing apparatus comprising: The substrate processing apparatus according to claim 1,
The first driving means supplies the substrate holding means for holding the substrate in the second state after supplying pure water to the surface of the substrate by the second supply means in the second state. And a third rotation speed that is higher than the second rotation speed and the second rotation speed. The substrate processing apparatus according to claim 1 or 2, wherein
The substrate processing apparatus, wherein the second driving unit moves the collection member in the vertical direction with respect to the substrate holding unit. The substrate processing apparatus according to claim 1 or 2, wherein
The substrate processing apparatus, wherein the second driving unit moves the substrate holding unit in a vertical direction with respect to the recovery member. A substrate processing apparatus according to any one of claims 1 to 4,
The substrate processing apparatus, wherein the first supply means and the second supply means are shared by one supply means. A substrate processing apparatus according to any one of claims 1 to 5,
The side of the processing chamber has an opening for transporting the substrate, and the height of the substrate holding means in the second state and the opening of the processing chamber are the same. Substrate processing equipment.

Images